PEP-0318, @decorator-style. In Guido's words:

"@ seems the syntax that everybody can hate equally"
Implementation by Mark Russell, from SF #979728.

Lib/symbol.py

@@ -13,75 +13,77 @@
 single_input = 256
 file_input = 257
 eval_input = 258
-funcdef = 259
-parameters = 260
-varargslist = 261
-fpdef = 262
-fplist = 263
-stmt = 264
-simple_stmt = 265
-small_stmt = 266
-expr_stmt = 267
-augassign = 268
-print_stmt = 269
-del_stmt = 270
-pass_stmt = 271
-flow_stmt = 272
-break_stmt = 273
-continue_stmt = 274
-return_stmt = 275
-yield_stmt = 276
-raise_stmt = 277
-import_stmt = 278
-import_as_name = 279
-dotted_as_name = 280
-dotted_name = 281
-global_stmt = 282
-exec_stmt = 283
-assert_stmt = 284
-compound_stmt = 285
-if_stmt = 286
-while_stmt = 287
-for_stmt = 288
-try_stmt = 289
-except_clause = 290
-suite = 291
-test = 292
-and_test = 293
-not_test = 294
-comparison = 295
-comp_op = 296
-expr = 297
-xor_expr = 298
-and_expr = 299
-shift_expr = 300
-arith_expr = 301
-term = 302
-factor = 303
-power = 304
-atom = 305
-listmaker = 306
-testlist_gexp = 307
-lambdef = 308
-trailer = 309
-subscriptlist = 310
-subscript = 311
-sliceop = 312
-exprlist = 313
-testlist = 314
-testlist_safe = 315
-dictmaker = 316
-classdef = 317
-arglist = 318
-argument = 319
-list_iter = 320
-list_for = 321
-list_if = 322
-gen_iter = 323
-gen_for = 324
-gen_if = 325
-testlist1 = 326
-encoding_decl = 327
+decorator = 259
+decorators = 260
+funcdef = 261
+parameters = 262
+varargslist = 263
+fpdef = 264
+fplist = 265
+stmt = 266
+simple_stmt = 267
+small_stmt = 268
+expr_stmt = 269
+augassign = 270
+print_stmt = 271
+del_stmt = 272
+pass_stmt = 273
+flow_stmt = 274
+break_stmt = 275
+continue_stmt = 276
+return_stmt = 277
+yield_stmt = 278
+raise_stmt = 279
+import_stmt = 280
+import_as_name = 281
+dotted_as_name = 282
+dotted_name = 283
+global_stmt = 284
+exec_stmt = 285
+assert_stmt = 286
+compound_stmt = 287
+if_stmt = 288
+while_stmt = 289
+for_stmt = 290
+try_stmt = 291
+except_clause = 292
+suite = 293
+test = 294
+and_test = 295
+not_test = 296
+comparison = 297
+comp_op = 298
+expr = 299
+xor_expr = 300
+and_expr = 301
+shift_expr = 302
+arith_expr = 303
+term = 304
+factor = 305
+power = 306
+atom = 307
+listmaker = 308
+testlist_gexp = 309
+lambdef = 310
+trailer = 311
+subscriptlist = 312
+subscript = 313
+sliceop = 314
+exprlist = 315
+testlist = 316
+testlist_safe = 317
+dictmaker = 318
+classdef = 319
+arglist = 320
+argument = 321
+list_iter = 322
+list_for = 323
+list_if = 324
+gen_iter = 325
+gen_for = 326
+gen_if = 327
+testlist1 = 328
+encoding_decl = 329
 #--end constants--
 
 sym_name = {}